Hi Kirill,
which version of wM are you running on?
Which version of JDBC Adapter are you using?
Any Fixes applied to them?
Regarding the driver:
Please do not use both jars together.
Depending on the wM version (and the Jave version it is running on) you will only need either the jre8 (for java version 8+) or the jre11 (for java version 11+) variant.
Remember to import the driver classes in your java service.
When updating drivers in the JDBC Adapters code/jars/ folder, remember to reload the adapter package to activate them.
When your algorithm is involving multiple calls, you can try to split these into several adapter services then.
Or you can implement the algorithm in a StoredProcedure and invoke this from corresponding AdapterServiceTemplate.
Regards,
Holger